Extremely high head and suction pressures

Originally had the same conditions above and came to the conclusion that the evap coil had blockage (we tried several times to clear it) and then removed all the refrigerant, swapped out the evap coil (used nitrogen while brazing), did a pressure test and vacuum test, and recharged with new refrigerant -- note: evap coil uses a piston metering device and we reinstalled the same one -- during the beginning of the recharging process the pressures and temps seemed to be ok but then the hissing noise at the condenser (bypass) started and after a few minutes the head pressure climbed way up and the suction did not follow -- but after we shut off the unit the head remained high and the suction followed -- after a few more minutes the head pressure dropped and the suction pressure remained high -- if the unit is powered back on then the cycle repeats itself -- so we're not sure what to check from here -- I suspected the condensing unit filter/dryer but the temps on either side of the device are not drastic

american standard model # wch024b100aa heat pump. starts ok then my head pressure go's real high and my low side go's down then it comes back down and repeats it's self till it trip over load. could it be my txvs or reversing valve going bad?american standard model # wch024b100aa heat pump. starts ok then my head pressure go's real high and my low side go's down then it comes back down and repeats it's self till it trip over load. could it be my txvs or reversing valve going bad?

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Testing the system an not replacing parts is the way to find the problem . Without knowing how ,using a factory diagnostic flow chart to go by would be best for a rookie .
System Description
The control module tests the evaporative emission (EVAP) system for a large leak. The control module monitors the fuel tank pressure (FTP) sensor signal to determine the EVAP system vacuum level. When the conditions for running are met, the control module commands the EVAP canister purge valve OPEN and the EVAP vent valve CLOSED . This allows engine vacuum to enter the EVAP system. At a calibrated time, or vacuum level, the control module commands the EVAP canister purge valve closed, sealing the system, and monitors the FTP sensor input in order to determine the EVAP system vacuum level. If the system is unable to achieve the calibrated vacuum level, or the vacuum level decreases too rapidly, this DTC sets.

Conditions For Setting the DTC
The EVAP system is not able to achieve or maintain vacuum during the diagnostic test.
Diagnostic Aids
• To help locate intermittent leaks, use the J 41413-200 Evaporative Emissions System Tester (EEST) to introduce smoke into the EVAP system. Move all EVAP components while observing smoke with the J 41413-SPT High Intensity White Light.
• A temporary blockage in the EVAP purge solenoid, purge pipe or EVAP canister could cause an intermittent condition. Inspect and repair any restriction in the EVAP system.
• To improve the visibility of the smoke exiting the EVAP system, observe the suspected leak area from different angles with theJ 41413-SPT .
• Reviewing the Failure Records vehicle mileage since the diagnostic test last failed may help determine how often the condition that caused the DTC to be set occurs. This may assist in diagnosing the condition.
• For intermittent conditions refer to Intermittent Conditions .

Inspect the EVAP system for the following conditions:
• A loose, missing, or damaged service port schrader valve
• A loose, incorrect, missing, or damaged fuel fill cap
• A damaged EVAP purge solenoid
Raise the vehicle on a hoist. Refer to Lifting and Jacking the Vehicle in General Information.
Inspect the EVAP system for the following conditions:
• Any disconnected, improperly routed, kinked, or damaged EVAP pipes and hoses
• A damaged EVAP vent solenoid or EVAP canister
Did you find and correct the condition?

Smoke testing the evap system to find the leak would be your best bet .

Possible Causes
There are several reasons for a compressor to run too hot, including high compression ratio, high return gas temperatures, and lack of external cooling.High compression ratios are the result of either lower than normal suction pressures or higher than normal discharge pressures. Changes in suction pressure will affect the compression ratio more rapidly than changes in the discharge pressure. For this reason, it is important to keep the suction pressure at its highest possible value.
Causes of low suction pressure can include incorrect sizing of components, misadjusted or defective metering devices (TXVs), loss of refrigerant charge, plugged driers or strainers, and excessive suction line pressure drop.
Although not as sensitive to change as the suction pressure, the discharge pressure can still greatly affect the compression ratio. Keeping the discharge pressure within normal operating conditions is still important.
Causes of high discharge pressure can include dirty condensing coils, undersized discharge line, a blockage or recirculation of condenser air, erratic condenser fan operation, refrigerant overcharge, noncondensibles in the system, and an undersized condenser.
Many larger refrigeration systems with electronic controllers will automatically monitor the temperature of the discharge line and will send out an alarm to alert the owner or service contractor of a potential problem. Regardless of how the discharge line temperature is monitored, it should always be checked as part of any service to a refrigeration system.
A technician should also check the discharge line temperature within 6 inches from the outlet of the compressor. Any temperature above 225 degrees should be investigated and the cause found and repaired.

A fuel fill cap that is left OFF after a fuel fill will cause this DTC to set.A loose, missing, or damaged fuel fill cap can cause this DTC to set.A blockage or restriction in the EVAP purge solenoid, purge pipe EVAP canister, or vapor pipe, can cause this DTC to set.A temporary blockage in the EVAP purge solenoid, purge pipe, or EVAP canister could cause an intermittent condition. Inspect and repair any restriction in the EVAP system.To help locate intermittent leaks, use the J 41413-200 to introduce smoke into the EVAP system. Move all EVAP components while observing smoke with the J 41413-SPT .To improve the visibility of the smoke exiting the EVAP system, observe the suspected leak area from different angles with the J 41413-SPT .Observe the Freeze Frame/Failure Records vehicle mileage since the diagnostic test last failed may help determine how often the condition occurs that caused the DTC to set . This may assist in diagnosing the condition.

The EVAP system tests run when the engine is first started and meets the Conditions for Running the DTC. An intermittent condition could be caused by a damaged EVAP vent housing, a temporary blockage at the EVAP canister vent inlet, or a pinched vent hose. A blockage in the vent system will also cause a poor fuel fill condition.An EVAP canister, vent hose, or vent solenoid valve that has restricted flow may cause this DTC to set. Using a purge solenoid command with a scan tool will allow vacuum to be applied to the system instead of pressure. With the engine running, the EVAP canister vent solenoid valve open and the EVAP canister purge solenoid valve commanded to 100 percent, the fuel tank vacuum should not increase to more than 5 inches H2O.An EVAP canister filter that is restricted can cause this DTC to set. Refer to Evaporative Emission (EVAP) Canister Filter Replacement and Evaporative Emission (EVAP) System Cleaning .Disconnecting one component at a time while the EVAP system is under flow will help to pinpoint a restriction in the system.Reviewing the Failure Records vehicle mileage since the diagnostic test last failed may help determine how often the condition that caused the DTC to be set occurs. This may assist in diagnosing the condition.For intermittent conditions, refer to Intermittent Conditions .

Hello, typiccally with noncondensables in the system your head pressure would be alot higher. 175 is pretty low high side pressure. Usually coils will freeze due to either low airflow or low refrigersmt charge not becuase of non condensables. I would get a second opinion from a differant company.

The Powertrain Control Module (PCM) supplies a ground to energize the valve (purge ON). The EVAP purge valve control is Pulse Width Modulated (PWM) or turned ON and OFF several times a second. The duty cycle (pulse width) is determined by engine operating conditions including load, throttle position, coolant temperature and ambient temperature. The duty cycle is calculated by the PCM and the output is commanded when the appropriate conditions have been met. The system checks for conditions that cause the EVAP system to purge continuously by commanding the EVAP canister vent valve ON and the EVAP purge valve OFF (EVAP canister vent valve CLOSED, EVAP purge PWM 0%). If vacuum level in the fuel tank increases during the test, a continuous purge flow condition is indicated. This can be caused by any of the following conditions:

EVAP purge valve leaking.EVAP purge and engine vacuum lines switched at the EVAP purge valve.EVAP purge valve control circuit grounded. If any of these conditions are present, DTC P1441 will set.

The PCM will illuminate the Malfunction Indicator Lamp (MIL) during the first trip in which the diagnostic test has been run and failed.The PCM will store conditions which were present when the DTC set as Freeze Frame and Fail Records data.

NOTE: Although these diagnostics are considered type A, they act like type B diagnostics under certain conditions. Whenever the EVAP diagnostics report that the system has passed, or if the battery has been disconnected, the diagnostic must fail during two consecutive cold start trips before setting a DTC. The initial failure is not reported to the diagnostic executive or displayed on a scan tool. A passing system always reports to the diagnostic executive immediately.

CONDITIONS FOR CLEARING THE MIL/DTC

The PCM will turn the MIL OFF during the third consecutive trip in which the diagnostic has been run and passed.

The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.The DTC can be cleared by using the scan tool Clear Info function or by disconnecting the PCM battery feed.

DIAGNOSTIC AIDS Check for the following conditions:

Poor connection at the PCM.Inspect harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and poor terminal to wire connection.

Damaged harness.Inspect the wiring harness for damage.

If the harness appears to be OK, connect the J 41413 EVAP pressure/purge diagnostic station to the EVAP service port, pressurize the EVAP system to 10 in. H2O and observe the Fuel Tank Pressure display on the scan tool while moving connectors and wiring harnesses related to the EVAP purge valve. A sudden change in the display will indicate the location of the malfunction.Incorrect vacuum line routing.Verify that the source vacuum line routing to the EVAP purge valve is correct and that the EVAP purge and source vacuum lines to the EVAP purge solenoid are not switched.

Malfunctioning or damaged canister.A malfunctioning canister may intermittently allow charcoal into the EVAP purge solenoid, vacuum switch, and associated lines causing a DTC to be set. Use the following procedure to check for a carbon release condition:

Turn OFF the ignition switch.Remove the EVAP purge valve.Lightly tap the EVAP purge valve and (if applicable) the vacuum switch on a clean work area looking for carbon particles exiting either of the vacuum ports.If no carbon release is evident, reinstall the components and continue with the DTC P1441 table. If carbon is being released from either component, continue with this service procedure.Remove the charcoal canister from the vehicle.Ensure that the main cylinder valve is turned off on the J 41413 EVAP purge/pressure diagnostic station.Disconnect the black hose that connects the nitrogen cylinder to the EVAP purge/pressure diagnostic station at the pressure regulator by unscrewing the knurled nut on the regulator. No tools are required to remove the black hose from the regulator.Using a section of vacuum line, connect one end over the open threaded fitting of the EVAP purge/pressure diagnostic station pressure regulator.Connect the remaining end to the EVAP purge valve end of the EVAP purge line at the vehicle and turn on the main nitrogen cylinder valve. Continue to blow any debris from the purge line for 15 seconds.Return the EVAP Pressure/Purge Diagnostic Station to its original condition by re-installing the black hose that was disconnected in step 7.Replace the following components:The EVAP purge valve.The EVAP canister.Proceed with the the DTC P1441 diagnostic table.Reviewing the Fail Records vehicle mileage since the diagnostic test last failed may help determine how often the condition that caused the DTC to set occurs. This may assist in diagnosing the condition.

TEST DESCRIPTION Number(s) below refer to the step number(s) on the Diagnostic Table.

If an EVAP purge valve electrical malfunction is present, the purge system will not operate correctly. Repairing the electrical malfunction will very likely correct the condition that set DTC P1441.Checks the Fuel Tank Pressure sensor at ambient pressureChecks for a stuck open EVAP purge valve.Verifies that the fuel tank pressure sensor accurately reacts to EVAP system pressure changes.If the EVAP purge and engine vacuum lines are switched at the EVAP purge solenoid, the solenoid valve will leak vacuum.The PCM will command the EVAP purge and EVAP canister vent valves closed with the scan tool Seal System EVAP output control function activated. Fuel tank pressure should not decrease under this condition.

The control module tests the evaporative emission (EVAP) system for a large leak. The control module monitors the fuel tank pressure (FTP) sensor signal to determine the EVAP system vacuum level. When the conditions for running are met, the control module commands the EVAP canister purge solenoid valve open and the EVAP canister vent solenoid valve closed. This allows engine vacuum to enter the EVAP system. At a calibrated time, or vacuum level, the control module commands the EVAP canister purge solenoid valve closed, sealing the system, and monitors the FTP sensor input in order to determine the EVAP system vacuum level. If the system is unable to achieve the calibrated vacuum level, or the vacuum level decreases too rapidly, this DTC sets.The table illustrates the relationship between the ON and OFF states, and the Open or Closed states of the EVAP canister purge and vent solenoid valves.

CONDITIONS FOR SETTING THE DTC The EVAP system is not able to achieve or maintain vacuum during the diagnostic test.

ACTION TAKEN WHEN THE DTC SETSThe control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

CONDITIONS FOR CLEARING THE MIL/DTCThe control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.A current DTC, Last Test Failed, clears when the diagnostic runs and passes.A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.Clear the MIL and the DTC with a scan tool.

DIAGNOSTIC AIDSTo help locate intermittent leaks, use the J 41413-200 Evaporative Emission System Tester (EEST) to introduce smoke into the EVAP system. Move all EVAP components while observing smoke with the J 41413-SPT High Intensity White Light. Introducing smoke in 15-second intervals will allow less pressure into the EVAP system. When the system is less pressurized, the smoke will sometimes escape in a more condensed manner.A temporary blockage in the EVAP canister purge solenoid valve, purge pipe, or EVAP canister could cause an intermittent condition. Inspect and repair any restriction in the EVAP system.To improve the visibility of the smoke exiting the EVAP system, observe the suspected leak area from different angles with the J 41413-SPT.Reviewing the Failure Records vehicle mileage since the diagnostic test last failed may help determine how often the condition that caused the DTC to be set occurs. This may assist in diagnosing the condition.For intermittent conditions, refer to Testing for Intermittent Conditions and Poor Connections. See: Diagrams\Diagnostic Aids

TEST DESCRIPTIONNumbers below refer to the step numbers on the diagnostic table.Introducing smoke in 15-second intervals may allow smaller leak areas to be more noticeable. When the system is less pressurized, the smoke will sometimes escape in a more condensed manner.This step verifies proper operation of the FTP sensor.A normal operating FTP sensor should increase above 5 inches of H2O and stop between 6-7 inches of H2O.Fig: 01Fig. 02Fig. 03

DTC P0455 - Evaporative Emission (EVAP) System Large Leak DetectedThe control module tests the evaporative emission (EVAP) system for a large leak. The control module monitors the fuel tank pressure (FTP) sensor signal to determine the EVAP system vacuum level. When the conditions for running are met, the control module commands the EVAP canister purge solenoid valve open and the EVAP canister vent solenoid valve closed. This allows engine vacuum to enter the EVAP system. At a calibrated time, or vacuum level, the control module commands the EVAP canister purge solenoid valve closed, sealing the system, and monitors the FTP sensor input in order to determine the EVAP system vacuum level. If the system is unable to achieve the calibrated vacuum level, or the vacuum level decreases too rapidly, this DTC sets.

DTC P0455 runs once per cold start.CONDITIONS FOR SETTING THE DTC The EVAP system is not able to achieve or maintain vacuum during the diagnostic test.

ACTION TAKEN WHEN THE DTC SETSThe control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.CONDITIONS FOR CLEARING THE MIL/DTCThe control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.A current DTC, Last Test Failed, clears when the diagnostic runs and passes.A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.Clear the MIL and the DTC with a scan tool.DIAGNOSTIC AIDSTo help locate intermittent leaks, use the J 41413-200 Evaporative Emission System Tester (EEST) to introduce smoke into the EVAP system. Move all EVAP components while observing smoke with the J 41413-SPT High Intensity White Light. Introducing smoke in 15-second intervals will allow less pressure into the EVAP system. When the system is less pressurized, the smoke will sometimes escape in a more condensed manner.A temporary blockage in the EVAP canister purge solenoid valve, purge pipe, or EVAP canister could cause an intermittent condition. Inspect and repair any restriction in the EVAP system.To improve the visibility of the smoke exiting the EVAP system, observe the suspected leak area from different angles with the J 41413-SPT.Reviewing the Failure Records vehicle mileage since the diagnostic test last failed may help determine how often the condition that caused the DTC to be set occurs. This may assist in diagnosing the condition.

Numbers below refer to the step numbers on the diagnostic table.Introducing smoke in 15-second intervals may allow smaller leak areas to be more noticeable. When the system is less pressurized, the smoke will sometimes escape in a more condensed manner.This step verifies proper operation of the FTP sensor.A normal operating FTP sensor should increase above 5 inches of H2O and stop between 6-7 inches of H2O.

DTC P0411 - Secondary Air Injection System Incorrect

What I would do is on the pump (which is wright next to the battery in that area) find the 2 wire connector with a green and blk wire, if you apply 12 volts to the green wire the pump should come on the blk wire is grounded. The check valves have a high failure rate it comes right off the pump and can be bought separate. So if the pump runs put a check valve in it, if the pump doesn't run put a pump in it (not likely) This issue is not going to let the leave you sitting but you want to fix it before any emission testing. You may have some luck finding parts on line if Autozone can not.

Hope this helps; also keep in mind that your feedback is important and I`ll appreciate your time and consideration if you leave some testimonial comment about this answer.

Your head pressure is a little high, depending on the ambient temp and your suction pressure is a little low. The suction pressure should be around 68 psig, the equivalent of a 40 degree coil. You can try adding a little refrigerant, check your compressor amp draw. If head pressure keeps going up and suction doesn't come up you may have a restricted metering device or filter dryer